Contacts of the helix formed by residues 431 - 455 (chain B) in PDB entry 5YD6


Residue contacts within the protein are derived with the CSU software (Sobolev V., Sorokine A., Prilusky J., Abola E.E. and Edelman M. (1999) Automated analysis of interatomic contacts in proteins. Bioinformatics, 15, 327-332). A short description of the analytical approach is given at the end of the page.
For CSU analysis of other PDB entry

Note:
Non-standard 3 letter residue codes indicate a heterogroup. To identify and analyse, use LPC software

Legend:
Dist - nearest distance (Å) between atoms of two residues
Surf - contact surface area (Å2) between two residues
HB   - hydrophilic-hydrophilic contact (hydrogen bond)
Arom - aromatic-aromatic contact
Phob - hydrophobic-hydrophobic contact
DC   - hydrophobic-hydrophilic contact (destabilizing contact)
+/-  - indicates presence/absence of a specific contacts
*    - indicates residues forming contacts  by their side chain
       (including CA atoms)
Residues in contact with PRO 431 (chain B).
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    429B  ASP      4.2     2.9    -      -       -      +
    430B  LEU*     1.4    85.8    -      -       +      +
    432B  LYS*     1.3    67.2    +      -       -      +
    433B  ALA*     4.3     5.2    -      -       +      +
    434B  ASP*     2.8    34.4    +      -       -      +
    435B  GLN      3.0     9.5    +      -       -      -
    519B  LYS*     4.2    20.4    -      -       +      +
    520B  GLU*     3.7    35.0    -      -       +      +
----------------------------------------------------------
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Residues in contact with LYS 432 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    418B  ARG*     5.0    10.5    -      -       -      +
    422B  GLU*     5.5     5.3    +      -       -      -
    430B  LEU      3.4     2.2    +      -       -      -
    431B  PRO*     1.3    70.1    -      -       -      +
    433B  ALA*     1.3    56.6    +      -       -      +
    435B  GLN*     3.1    27.7    +      -       +      +
    436B  ASP*     2.9    60.4    +      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 433 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    431B  PRO*     3.1     1.7    -      -       +      +
    432B  LYS*     1.3    78.3    -      -       -      +
    434B  ASP*     1.3    59.8    +      -       -      +
    436B  ASP*     3.7     9.7    +      -       -      +
    437B  LEU*     3.0    27.2    +      -       -      +
    519B  LYS*     3.8    35.9    -      -       +      +
----------------------------------------------------------
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Residues in contact with ASP 434 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    430B  LEU*     4.1    16.2    -      -       +      +
    431B  PRO*     2.8    26.4    +      -       +      +
    433B  ALA*     1.3    75.7    -      -       -      +
    435B  GLN*     1.3    60.3    +      -       -      +
    437B  LEU*     3.7     2.3    -      -       -      +
    438B  LEU*     2.9    37.8    +      -       -      +
    517B  GLY      4.3     2.4    -      -       -      +
    518B  LEU*     3.5    22.7    -      -       +      +
    519B  LYS*     2.7    30.7    +      -       -      +
    520B  GLU*     2.9    31.5    +      -       -      +
    524B  VAL*     5.1     0.5    -      -       -      +
----------------------------------------------------------
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Residues in contact with GLN 435 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    422B  GLU*     4.2    17.8    +      -       -      +
    427B  PHE*     3.4    57.2    -      -       +      +
    428B  ALA*     3.7    18.0    -      -       -      +
    430B  LEU*     2.9    22.5    -      -       +      +
    431B  PRO      3.0    10.0    +      -       -      +
    432B  LYS*     3.1    30.2    +      -       +      +
    434B  ASP*     1.3    77.4    -      -       -      +
    436B  ASP*     1.3    57.7    +      -       -      +
    438B  LEU      3.4     0.2    +      -       -      -
    439B  PHE*     2.9    34.0    +      -       -      +
----------------------------------------------------------
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Residues in contact with ASP 436 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    418B  ARG*     4.6    10.9    +      -       -      +
    432B  LYS*     2.9    53.2    +      -       -      +
    433B  ALA*     3.8     8.0    -      -       -      +
    435B  GLN*     1.3    71.6    -      -       -      +
    437B  LEU*     1.3    64.3    +      -       -      +
    439B  PHE*     4.0     3.5    -      -       -      +
    440B  GLU*     2.9    50.3    +      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 437 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    433B  ALA      3.0    17.5    +      -       -      +
    434B  ASP*     3.7     5.4    -      -       -      +
    436B  ASP*     1.3    80.3    -      -       -      +
    438B  LEU*     1.3    56.1    +      -       -      +
    440B  GLU*     4.2     4.4    -      -       +      +
    441B  SER*     2.9    48.4    +      -       -      +
    515B  ARG*     4.2    12.3    -      -       +      -
    516B  HIS      3.5    22.7    -      -       -      +
    517B  GLY*     3.5    29.8    -      -       -      +
    518B  LEU*     3.7    17.7    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 438 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    427B  PHE*     3.8    13.7    -      -       +      -
    430B  LEU*     3.5    32.3    -      -       +      -
    434B  ASP      2.9    20.8    +      -       -      +
    435B  GLN      3.9     2.7    -      -       -      +
    437B  LEU*     1.3    70.8    -      -       -      +
    439B  PHE*     1.3    66.4    +      -       -      +
    441B  SER*     4.0     3.5    -      -       -      -
    442B  ALA*     3.3    25.3    +      -       -      +
    511B  MET*     3.5    27.6    -      -       +      +
    512B  VAL*     4.8     6.7    -      -       +      -
    513B  THR      3.4    25.8    -      -       -      +
    515B  ARG*     4.0     9.9    +      -       +      -
    518B  LEU*     3.9    18.4    -      -       +      -
    524B  VAL*     4.0    15.9    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 439 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    414B  MET*     3.4    37.0    -      -       +      -
    417B  ILE*     3.6    23.1    -      -       +      -
    418B  ARG*     3.4    70.7    -      -       +      +
    421B  ALA*     4.7     1.8    -      -       +      -
    427B  PHE*     4.7     4.5    -      -       +      -
    435B  GLN      2.9    21.2    +      -       -      +
    436B  ASP*     4.0     1.8    -      -       -      +
    438B  LEU*     1.3    72.7    -      -       -      +
    440B  GLU*     1.3    68.2    +      -       +      +
    442B  ALA*     3.3     1.7    +      -       -      +
    443B  PHE*     2.8    44.9    +      +       +      -
    446B  LEU*     4.9     0.5    -      -       -      +
    511B  MET*     3.8    19.9    -      -       -      +
    591B  LEU*     4.9     2.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with GLU 440 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    418B  ARG*     4.3     8.3    +      -       -      +
    436B  ASP*     2.9    41.8    +      -       -      +
    437B  LEU*     4.2     4.2    +      -       +      +
    439B  PHE*     1.3    89.0    -      -       +      +
    441B  SER*     1.3    60.0    +      -       -      +
    443B  PHE*     3.6     4.6    +      -       -      +
    591B  LEU*     3.6    35.5    -      -       +      +
    594B  ASP*     6.1     1.0    -      -       -      +
    595B  THR*     5.4     4.9    -      -       -      +
    601B  8SU      2.9    33.9    +      -       -      +
----------------------------------------------------------
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Residues in contact with SER 441 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    437B  LEU*     2.9    37.9    +      -       -      +
    438B  LEU      4.0     0.9    -      -       -      -
    439B  PHE      3.4     0.2    -      -       -      -
    440B  GLU*     1.3    76.7    -      -       -      +
    442B  ALA*     1.3    57.5    +      -       -      +
    445B  GLU*     3.7    11.6    -      -       -      +
    515B  ARG*     3.4    35.2    +      -       -      -
    595B  THR*     5.9     1.8    -      -       -      -
    601B  8SU      3.3    42.4    -      -       -      +
----------------------------------------------------------
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Residues in contact with ALA 442 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    438B  LEU      3.3    17.2    +      -       -      +
    439B  PHE      3.6     0.4    -      -       -      +
    440B  GLU      3.2     0.4    -      -       -      -
    441B  SER*     1.3    77.6    -      -       -      +
    443B  PHE*     1.3    65.6    +      -       -      +
    444B  LEU      3.4     2.2    -      -       -      -
    445B  GLU*     3.1    12.7    +      -       +      +
    446B  LEU*     2.8    35.3    +      -       +      +
    510B  ALA      3.4    27.1    -      -       -      +
    511B  MET*     3.7    10.1    -      -       -      -
    515B  ARG*     3.7     4.7    -      -       -      +
----------------------------------------------------------
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Residues in contact with PHE 443 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    410B  LEU*     3.3    32.3    -      -       +      -
    413B  SER*     3.4    22.4    -      -       -      -
    414B  MET*     3.6    36.3    -      -       +      -
    417B  ILE*     4.0    10.1    -      -       +      -
    439B  PHE*     2.8    43.8    +      +       +      +
    440B  GLU*     4.0     4.3    -      -       -      +
    442B  ALA*     1.3    76.5    -      -       -      +
    444B  LEU*     1.3    79.0    +      -       +      +
    446B  LEU*     3.3     7.9    +      -       -      +
    447B  PHE*     2.9    31.5    +      -       +      +
    591B  LEU*     4.9     2.2    -      -       +      -
    601B  8SU      3.5    26.2    +      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 444 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    410B  LEU*     4.1    15.5    -      -       +      -
    442B  ALA      3.4     0.2    -      -       -      -
    443B  PHE*     1.3    90.6    -      -       +      +
    445B  GLU*     1.3    65.6    +      -       -      +
    447B  PHE*     3.4     4.1    +      -       +      +
    448B  VAL*     3.0    31.0    +      -       -      +
    482B  TRP*     3.9    24.5    -      -       +      -
    566B  CYS*     3.6    38.4    -      -       +      +
    569B  GLY*     4.4     2.9    -      -       -      -
    570B  LEU*     3.8    32.3    -      -       +      +
    573B  ILE*     4.9     3.8    -      -       +      -
    601B  8SU      3.1    31.6    +      -       +      +
----------------------------------------------------------
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Residues in contact with GLU 445 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    441B  SER      3.7    18.4    -      -       -      +
    442B  ALA*     3.1    10.4    +      -       -      +
    444B  LEU*     1.3    77.4    -      -       -      +
    446B  LEU*     1.3    57.1    +      -       -      +
    448B  VAL*     3.4     2.0    +      -       -      -
    449B  LEU*     2.9    30.9    +      -       -      +
    510B  ALA*     5.0    12.4    -      -       +      +
    515B  ARG*     4.2    14.5    +      -       -      -
    559B  LEU      3.9     6.2    -      -       -      +
    562B  LEU*     3.4    55.0    -      -       +      +
    563B  ARG*     3.7    12.4    +      -       -      +
    566B  CYS*     3.8    10.5    -      -       +      +
    601B  8SU      4.2     8.0    -      -       -      +
----------------------------------------------------------
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Residues in contact with LEU 446 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    417B  ILE*     3.7    26.5    -      -       +      -
    420B  TRP*     3.6    29.4    -      -       +      -
    439B  PHE*     4.9     2.2    -      -       +      +
    442B  ALA*     2.8    41.3    +      -       +      +
    443B  PHE*     3.7     5.2    -      -       -      +
    445B  GLU*     1.3    69.4    -      -       -      +
    447B  PHE*     1.3    61.1    +      -       -      +
    449B  LEU*     4.4     5.2    -      -       +      -
    450B  ARG*     2.9    40.8    +      -       -      +
    507B  ALA*     3.2    36.3    -      -       +      +
    510B  ALA*     4.0    11.4    -      -       +      -
    511B  MET*     4.1    10.8    -      -       +      -
----------------------------------------------------------
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Residues in contact with PHE 447 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    409B  LEU*     4.4     7.2    -      -       +      -
    410B  LEU*     3.8    23.8    -      -       +      -
    413B  SER*     3.4    33.0    -      -       -      +
    417B  ILE*     3.7     9.6    -      -       +      +
    443B  PHE*     2.9    23.0    +      -       +      +
    444B  LEU*     3.6     6.5    -      -       +      +
    446B  LEU*     1.3    75.4    -      -       -      +
    448B  VAL*     1.3    76.4    +      -       +      +
    450B  ARG*     4.3     1.9    -      -       -      +
    451B  LEU*     3.2    47.7    +      -       +      +
    454B  ARG*     5.1     4.9    +      -       -      -
    464B  PHE*     4.2    16.4    -      +       -      -
    479B  PHE*     3.9    28.0    -      +       -      -
    482B  TRP*     3.8    21.8    -      +       -      -
    486B  ILE*     4.5     1.6    -      -       +      -
----------------------------------------------------------
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Residues in contact with VAL 448 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    444B  LEU      3.0    17.9    +      -       -      +
    445B  GLU*     3.8     3.6    -      -       -      +
    447B  PHE*     1.3    81.9    -      -       +      +
    449B  LEU*     1.3    59.5    +      -       -      +
    451B  LEU*     3.4     4.3    +      -       -      +
    452B  ALA*     2.9    32.1    +      -       -      +
    482B  TRP*     3.4    32.5    -      -       +      +
    486B  ILE*     3.9    23.7    -      -       +      +
    489B  PHE*     4.2     7.6    -      -       +      -
    562B  LEU*     4.0    11.2    -      -       +      -
    565B  LEU*     3.9    32.5    -      -       +      +
----------------------------------------------------------
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Residues in contact with LEU 449 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    445B  GLU      2.9    18.0    +      -       -      +
    446B  LEU*     3.9     6.3    -      -       +      +
    448B  VAL*     1.3    77.4    -      -       -      +
    450B  ARG*     1.3    63.3    +      -       +      +
    452B  ALA*     3.4     5.1    +      -       -      +
    453B  TYR*     3.1    24.4    +      -       -      +
    489B  PHE*     4.2    17.0    -      -       +      -
    493B  LEU*     4.2    12.5    -      -       +      +
    503B  PHE*     3.6    24.6    -      -       +      -
    506B  ILE*     4.4    14.4    -      -       +      +
    507B  ALA*     3.6    37.0    -      -       +      +
    510B  ALA*     4.8     4.7    -      -       +      -
    558B  LYS*     5.4     2.5    -      -       +      -
    562B  LEU*     3.8    29.1    -      -       +      +
----------------------------------------------------------
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Residues in contact with ARG 450 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    372B  HIS*     4.6     2.8    -      -       +      -
    375B  SER*     2.7    47.4    +      -       -      -
    376B  ASN*     3.4    22.2    +      -       -      +
    416B  ILE*     3.4    18.2    -      -       -      +
    417B  ILE*     3.4    29.5    -      -       -      +
    420B  TRP*     4.0    19.3    -      -       -      +
    446B  LEU*     2.9    36.4    +      -       +      +
    447B  PHE*     4.4     1.8    -      -       -      +
    449B  LEU*     1.3    72.8    -      -       +      +
    451B  LEU*     1.3    62.0    +      -       -      +
    453B  TYR*     3.5     2.4    +      -       -      +
    454B  ARG*     3.1    47.4    +      -       -      +
    465B  CYS*     4.6     2.4    -      -       -      +
    503B  PHE*     4.1    21.8    -      -       +      -
    507B  ALA*     5.2     6.5    -      -       +      -
----------------------------------------------------------
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Residues in contact with LEU 451 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    447B  PHE*     3.2    48.7    +      -       +      +
    448B  VAL*     3.8     2.5    -      -       -      +
    450B  ARG*     1.3    73.3    -      -       -      +
    452B  ALA*     1.3    60.2    +      -       -      +
    454B  ARG*     3.2    13.6    +      -       -      +
    455B  SER*     2.6    51.1    +      -       -      +
    462B  LEU*     4.0    14.1    -      -       +      -
    463B  ILE      3.3    30.5    -      -       -      +
    464B  PHE*     3.9    23.8    -      -       +      -
    479B  PHE*     5.2     2.5    -      -       +      -
    483B  ILE*     5.8     0.4    -      -       +      -
    486B  ILE*     3.9    24.0    -      -       +      -
----------------------------------------------------------
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Residues in contact with ALA 452 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    448B  VAL*     2.9    18.9    +      -       +      +
    449B  LEU      3.6     4.7    -      -       -      +
    451B  LEU*     1.3    78.6    -      -       -      +
    453B  TYR*     1.3    55.9    +      -       -      +
    454B  ARG      3.6     0.2    +      -       -      -
    455B  SER*     3.9     1.2    +      -       -      -
    486B  ILE*     4.6     5.4    -      -       +      +
    489B  PHE*     3.6    29.8    -      -       +      -
    490B  SER*     2.5    43.0    +      -       -      +
    493B  LEU*     3.9     5.2    -      -       +      -
    494B  GLN*     3.0    12.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with TYR 453 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    372B  HIS*     4.1    17.0    -      +       -      -
    449B  LEU      3.1    18.0    +      -       -      +
    450B  ARG      3.9     2.9    -      -       -      +
    451B  LEU      3.3     0.2    -      -       -      -
    452B  ALA*     1.3    77.2    -      -       -      +
    454B  ARG*     1.3    58.7    +      -       -      +
    493B  LEU*     3.8    17.7    -      -       +      +
    494B  GLN*     3.3    20.8    -      -       +      +
    498B  ILE*     2.5    39.4    +      -       +      -
    499B  ASP      3.4    12.8    -      -       -      -
    500B  ILE*     3.5     2.9    +      -       +      -
    503B  PHE*     3.5    55.6    -      +       +      -
    370D  ARG*     3.1    33.6    +      -       -      -
----------------------------------------------------------
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Residues in contact with ARG 454 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    376B  ASN*     3.0    32.1    +      -       +      -
    377B  PRO*     3.6    19.1    -      -       +      +
    379B  MET*     3.7    20.3    -      -       -      +
    447B  PHE*     5.1     4.8    +      -       -      -
    450B  ARG*     3.1    35.6    +      -       -      +
    451B  LEU*     3.6    22.1    -      -       -      +
    453B  TYR*     1.3    76.0    -      -       -      +
    455B  SER*     1.3    65.5    +      -       -      +
    463B  ILE*     2.9    50.7    +      -       +      +
    464B  PHE*     3.4     4.4    -      -       -      +
    465B  CYS*     3.2    38.6    -      -       -      +
----------------------------------------------------------
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Residues in contact with SER 455 (chain B). Click here for Legend to table.
----------------------------------------------------------
                                  Specific contacts
                               ---------------------------
     Residue       Dist    Surf   HB    Arom    Phob    DC
----------------------------------------------------------
    451B  LEU*     2.6    31.4    +      -       -      +
    452B  ALA*     3.9     0.8    +      -       -      -
    453B  TYR      3.5     1.2    -      -       -      -
    454B  ARG*     1.3    82.1    -      -       -      +
    456B  ASN*     1.3    61.8    +      -       -      +
    457B  PRO*     3.4     3.9    -      -       -      +
    461B  LYS      3.1    13.5    -      -       -      -
    462B  LEU*     3.4     8.0    -      -       -      +
    463B  ILE*     3.1    25.6    +      -       -      +
    490B  SER*     4.1    13.5    -      -       -      -
    494B  GLN*     2.9    20.8    +      -       -      +
----------------------------------------------------------
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A short description of the analytical approach
The contact analysis used in this page is based upon the approach developed in: Sobolev V., Wade R.C., Vriend G. and Edelman M. PROTEINS (1996) 25, 120-129. Contact legitimacy depends on the hydrophobic-hydrophilic properties of the contacting atoms. In order to define it, for each inter-atomic contact, eight atom classes have been introduced:


   I  Hydrophilic      - N and O that can donate and accept hydrogen bonds
                         (e.g., oxygen of hydroxyl group of Ser. or Thr)
  II  Acceptor         - N or O that can only accept a hydrogen bond
 III  Donor            - N that can only donate a hydrogen bond
  IV  Hydrophobic      - Cl, Br, I and all C atoms that are not in
                         aromatic rings and do not have a covalent bond to
                         a N or O atom
   V  Aromatic         - C in aromatic rings irrespective of any other 
                         bonds formed by the atom
  VI  Neutral          - C atoms that have a covalent bond to at least one
                         atom of class I or two or more atoms from class II
                         or III; atoms; S, F, P, and metal atoms in all cases
 VII  Neutral-donor    - C atoms that have a covalent bond with only one
                         atom of class III
VIII  Neutral-acceptor - C atoms that have a covalent bond with only 
                         one atom of class II
For each pair of contacts the state of legitimacy is shown below:

Legend:
+, legitimate
-, illegitimate
------------------------------------------------------------
  Atomic class           I  II  III   IV   V   VI  VII  VIII
------------------------------------------------------------
   I  (Hydrophilic)      +   +    +    -   +   +    +    +
  II  (Acceptor)         +   -    +    -   +   +    +    -
 III  (Donor)            +   +    -    -   +   +    -    +
  IV  (Hydrophobic)      -   -    -    +   +   +    +    +
   V  (Aromatic)         +   +    +    +   +   +    +    +
  VI  (Neutral)          +   +    +    +   +   +    +    +
 VII  (Neutral-donor)    +   +    -    +   +   +    -    +
VIII  (Neutral-acceptor) +   -    +    +   +   +    +    -
------------------------------------------------------------
Warning!
Atom classes for heterogroups are automatically assigned based on the atomic coordinates. However, in three cases (see below) the automatic assignment is currently ambiguous. In these cases, the user is advised to manually analyse the full list of contacts using LPC software.
1. Carbon atoms belonging to a 4-, 5- or 6-member ring are 
   considered "aromatic" (Class V) if the ring is approximately
   planar, and "hydrophobic" (Class IV) or "neutral" (Classes
   VI, VII, VIII) if the ring is non-planar.
2. The oxygen atom of a carbonyl or hydroxy group is considered
   "hydroxy" (Class I) if the CO bond is longer than 1.29 Å, and
   "carbonyl" (Class II) if shorter.
3. All nitrogen atoms are considered "hydrophilic" (Class I).

Please E-mail any questions and/or suggestions concerning this page to Vladimir.Sobolev@weizmann.ac.il